More and more blog posts and articles are claiming that minimalist running is the best thing for the management of plantar fasciitis, most of which are from minimalist or barefoot runners who have no clinical experience actually treating the condition, yet seem to hold very strong clinical opinions (for example see this self-appointed expert). They may have had the condition themselves, but we do know that ineffective treatments sometimes work.
Minimalist and barefoot runners get plantar fasciitis and so do traditional running shoe wearers – just check around the barefoot and minimalist forums to see how many are asking for advice on it! Even those that promote minimalism have developed plantar fasciitis (see Pete Larsen & Once and Future Runner). If barefoot and minimalist runners get plantar fasciitis, then how can this be a solution for plantar fasciitis?
The reason most often cited as to why minimalism is the way to go for plantar fasciitis is not the evidence, but the belief that it is the best way to strengthen the muscles that is supposed to be needed to treat plantar fasciitis. As that “expert” says, “Strengthening the feet is critical for PF sufferers“. and as Mark Cucuzzella said, “the only way that you can actually fix plantar fasciitis is to address the root cause… weak foot muscles“. Are weak foot muscles really the cause of plantar fasciitis or do these people just wish it was the case? Wishful thinking is just another fallacy and does not make it true.
Those who want to promote minimalism for plantar fasciitis need to come up with some evidence that supports them and answer these questions:
- What actual evidence do you have for it? (especially in the context of the strength of the evidence for other treatment options for plantar fasciitis).
- Why have none of the risk factors studies on plantar fasciitis identified muscle weakness as a problem? In all the scientific literature on plantar fasciitis, muscle strength never even gets mentioned, let alone considered as an issue. (I did some ad hoc testing of muscle strength using a reliable and valid device that measures toe plantar flexion strength in 6 people with unilateral plantar fasciitis and could not find a muscle strength deficit on the plantar fasciitis side. I am the first to admit that this was no scientific study, but if muscle strength was an issue, don’t you think that this testing would have shown it?).
- As discussed here, barefoot or minimalism have not been shown to make the intrinsic muscles of the foot stronger anyway.
- Why is it that most clinicians who treat a lot of plantar fasciitis never think muscle strength is an issue? Why do the vast majority of plantar fasciitis cases get better without muscle strengthening? and without minimalism?
- Why do minimalist and barefoot runners get plantar fasciitis (see above)?
- Why does the typical non-runner with plantar fasciitis actually get more pain when they go barefoot? How can that be a good thing?
- Why does the only randomized controlled study on this show minimalism is worse than staying in the shoes that they got the injury in (see below)?
What does the evidence say?
One study has looked at this:
Examining the degree of pain reduction using a multielement exercise model with a conventional training shoe versus an ultraflexible training shoe for treating plantar fasciitis.
Ryan M, Fraser S, McDonald K, Taunton J.
Phys Sportsmed. 2009 Dec;37(4):68-74.
Plantar fasciitis is a common injury to the plantar aponeurosis, manifesting as pain surrounding its proximal insertion at the medial calcaneal tubercle. Pain is typically worse in the morning when getting out of bed, and may subside after the tissue is sufficiently warmed up. For running-based athletes and individuals who spend prolonged periods of time on their feet at work, plantar fasciitis may become recalcitrant to conservative treatments such as ice, rest, and anti-inflammatory medication. Exercise-based therapies have received only limited attention in the literature for this common problem, yet they are becoming increasingly validated for pain relief and positive tissue remodeling at other sites of similar soft-tissue overuse injury. This study reports on pain outcomes in individuals experiencing chronic plantar fasciitis whiles wearing a shoe with an ultraflexible midsole (Nike Free 5.0) (FREE) versus a conventional training (CON) shoe in a 12-week multielement exercise regimen, and after a 6-month follow-up. Adults with >/= 6-month history of painful heel pain were recruited and randomly assigned to wear 1 of the 2 shoes. All subjects completed the same exercise protocol. A visual analogue scale item tracked peak pain in the preceding 24 hours taken at baseline, 6- and 12-week points, and at the 6-month follow-up. Twenty-one subjects completed the program (9 FREE; 12 CON). Both groups reported significant improvements in pain by the 6-month follow-up, and the FREE group reported an overall reduced level of pain throughout the study as a result of lower mean pain scores at the midpoint and post-test compared with the CON group. The exercise regimen employed in this study appears to reduce pain associated with chronic plantar fasciitis, and in doing so, the Nike 5.0 shoe may result in reductions in pain earlier than conventional running shoes.
This study compared two groups of runners with plantar fasciitis. One group continued to use their original shoes and the other group used minimalist shoes (Nike Free). The authors claimed the results found no statistical difference between the groups but there was a trend: “the Nike 5.0 shoe may result in reductions in pain earlier than conventional running shoes.” However, what was not reported in the abstract was the dropouts in the minimalist group due to their symptoms getting so bad, so they withdrew from the study. The gold standard for the analysis and presenting the results of randomized controlled trials is to use what is called the intention to treat analysis (as recommended by the CONSORT statement and every textbook on randomized controlled trials). This means that the pain scores of the dropouts in the minimalist group should have been factored into the analysis. So, in reality, this study actually showed that the minimalist group did worse. I have already previously done an analysis of this study here.
The evidence from this study is that if you use minimalist shoes, you are probably going to get a worse outcome compared to staying in the shoes you got the injury in (which a lot of people change anyway!). What is an ethical evidence based clinician supposed to do? Do what the evidence says or do what some bloggers with no clinical experience say they should do?
Minimalism for Plantar Fasciitis?
I do not think foot strike pattern or running form actually has anything to do with plantar fasciitis (it does for other injuries). That is not because I don’t want it to be (wishful thinking), it is what the above tells me. I have no problems if a runner wants to do minimalism running or go barefoot, just don’t do it expecting that it will fix plantar fasciitis. There may be some compelling reasons to take up minimalistic or barefoot running, but plantar fasciitis is not one of them. I have previously done a pretty poor attempt at a satire on this here, that got republished here.
Of course some runners with plantar fasciitis who transition to barefoot or minimalism will find their plantar fasciitis symptoms improve at the same time and the same could happen if you go the other way, but that is more likely to be due to a change in the natural history of the condition (see: Why Ineffective Treatments Sometimes Work). Those symptoms may have improved at the same time if they had not transitioned. That is why we have randomized controlled studies to avoid falling into the natural history or placebo effects trap.
As always, I go where the evidence takes me until convinced otherwise
POSTSCRIPT: I just read Scott Douglass’s The Runners World Complete Guide to Minimalism and Barefoot Running (a good book!) and it mentions that a dramatic increase in the plantar fascia’s workload can lead to an immediate injury. He is right and it will. However, it is suggested that minimalism increases this load. If this is the case then how can minimalism be a good thing for plantar fasciitis? (Add that to the list of dot point questions above!). Having said that I do not believe the load going through the plantar fasica is any different when shod (generally) or not. I am very familiar with all the research on the plantar fascia (and have two publications on it myself!) and there is nothing in that body of literature that indicates that the plantar fascia is subjected to any greater loads when forefoot striking….again, just another case of wishful thinking and statement making that the uninformed believe to be true (because they want it to be true!) without any reference to the evidence. I will soon do a post on the plantar fascia and the windlass mechanism as it does keep coming up.
¹Additionally that same “expert” talked about above tells his blog readers: “Do not stretch the arch/PF directly, as this may only create a cycle of “tear and repair”“. If you should not do that, then how about explaining why this randomized control trial shows that this is exactly what you should be doing? Can you see the dangers of those with strong opinions about clinical conditions yet with no clinical experience and no knowledge of the scientific evidence are if they are let loose in the blogsphere and not be held accountable for their advice? No wonder so many cases of plantar fasciitis become chronic due to following such advice.
Ryan, M., Fraser, S., McDonald, K., & Taunton, J. (2009). Examining the Degree of Pain Reduction Using a Multielement Exercise Model with a Conventional Training Shoe Versus an Ultraflexible Training Shoe for Treating Plantar Fasciitis The Physician and Sportsmedicine, 37 (4), 68-74 DOI: 10.3810/psm.2009.12.1744